jcmd - executing multiple commands at the same safepoint?

[Thomas Stüfe]

Oh... maybe. You are right. And I see commas are not good either since
they are used in sub options (e.g. GC.class_stats).

Alternative ideas could be using brackets surrounding the
command-and-options (e.g. '{''}'):

jcmd  { GC.class_stats columns=InstBytes,KlassBytes }  { VM.metaspace
show-loaders }

I think technically we would not even need delimiters, since the
commands are as keywords limiting enough. E.g. one could just specify:

jcmd  GC.class_stats columns=InstBytes,KlassBytes VM.metaspace show-loaders

and that would be for jcmd too. It is more for the benefit of the user.

On Thu, May 10, 2018 at 7:54 AM, Kirk Pepperdine
<kirk.pepperdine at gmail.com> wrote:
> Awesome idea! Would the semicolon would be an issue for shell scripts?
>> On May 10, 2018, at 6:52 AM, Thomas Stüfe <thomas.stuefe at gmail.com> wrote:
>>
>> Hi all,
>>
>> just asking around for opinions.
>>
>> I am playing with the idea of bundling diagnostic commands to have
>> them executed at the same safepoint, in order to get results
>> consistent with each other.  E.g. a heapdump and a corresponding
>> metaspace statistic.
>>
>> Syntax wise, I think one could specify multiple commands in jcmd
>> separated by comma or semicola:
>>
>> jcmd <command> <option> <option>; <command 2> <option> <option>
>>
>> What do you think, would that be a useful addition?
>>
>> Thanks, Thomas
>